Cancer cure could come from patient’s immune system

A boost to your immune system could be all you need to cure cancer, if new developments in the US are anything to go by.

America’s Food and Drug Administration has approved an immunotherapy drug, called Keytruda, which stimulates the body’s immune system, for the first-line treatment of patients with metastatic, non-small-cell lung cancer.

This development is important for cancer patients around the world because it means chemotherapy may not be the first treatment one receives after being diagnosed with the disease. Immunotherapy treatment for cancer was first proposed by Dr William Colley in the 1890s, when he noticed that infections in cancer patients were sometimes associated with the disease regressing.

This discovery prompted him to speculate that intentionally producing an infection in a patient could help treat cancer.

To test the idea, he created a mixture of bacteria and used the cocktail to create infections in cancer patients in 1893. The bacteria would sometimes spur a patient’s immune system to attack not only the infection, but also anything else in the body that appeared “foreign”, including a tumor.

In one case, when Dr Coley injected streptococcal bacteria into a cancer patient to cause erysipelas — a bacterial infection in the skin — the patient’s tumor vanished, presumably because it was attacked by the immune system.

This idea was studied by various researchers in the 1900s but was not widely accepted as a cancer treatment approach. It wasn’t until the early 2000s that the hypothesis became more widely accepted, according to the Cancer Research Institute.

Immunotherapy comes in many forms — treatment vaccines, antibody therapies and drugs — and can be received through an injection, a pill or capsule, a topical ointment or cream, or a catheter.

This approach, however, has its downsides too, with the first being the high price of new immunotherapy drugs. Some estimates suggest that checkpoint inhibitor treatments could cost as much as Sh100 million per patient.

Scientists caution that doctors and patients alike should prepare for potential severe side effects and downsides, including skin reactions, flu-like symptoms, heart palpitations, diarrhoea, and arthritis in some patients. Experts are also trying to understand why some patients may have different responses to immunotherapy, including remissions instead of relapses.